Absorbent tampon

ABSTRACT

An absorbent tampon having a fluid pervious layer of polypropylene fibers disposed on its outer surface. Insertion force for such tampons is reduced more than 50 percent when compared with the insertion force required for conventional tampons.

United States Patent Olson et al. 1451 Aug. 15, 1972 (54] ABSORBENTTAMPON {56] References Cited 72 Inventors: Virglnla A. 01666; Bruce A.UNITED STATES PATENTS Townsend, h of hk h. Wi 2,902,03s 9/1959Bletzinger 6161. ....128/290 w 2,926,667 3/1960 Burger, Jr. etal.........l28/285 [73] fi 'zm s 3,416,526 12/1968Yeremian..............l28/296 x 3,420,235 1/1969 Harmon ..l28/285 22Filed: April 28, 1970 3,545,442 12/1970 Wicker 61al..............l28/296 [211 App! 29776 Prime/y Exanfiner-Charles F.Rosenbaum Related s A fl fi D, Attorney-Daniel J. Hanlon, Jr. andRaymond J.

M1] [63] Continuation of Ser. No. 708,575, Feb. 27, I at 1968,abandoned. [57] ABSTRACT 52 us. c1 128/285 abwbem having a mid Pmims 5In. a 13/20 polypropylene fibers disposed on its outer surface. In- [58]Field Jr s 1666111311.: 1111213563370 235 296 Such is than 50 percentwhen compared with the insertion force required for conventionaltampons.

8 Claims, 4 Drawing figures ABSORBENT TAMPON REFERENCE TO RELATEDAPPLICATION This application is a continuation of application Ser. No.708,575 filed Feb. 27, 1968 now abandoned.

BACKGROUND OF THE INVENTION Tampons have been used for internalabsorption of body fluids for many years, especially for catarnenialpurposes. The more common types of tampons in use today usually comprisea rectangular batt of absorbent material, such as cotton, cellulosewadding, synthetic sponge, cellulose fluff or combinations thereof,compressed to a cylindrical shape and a size small enough to fit intothe vaginal tract. The uncompressed batt may or may not be wrapped in afluid pervious web, depending on whether or not the batt contains shortor loose fibers. In compressed condition the tampons are preferably in aself-sustaining form, which form is substantially stable under normalatmospheric conditions but which expands readily when wetted. Thus,after a compressed tampon is inserted in the vaginal tract, the moistenvironment coupled with absorption of body fluids causes it to reexpandtoward its original uncompressed size into conforming engagement withthe walls of the vaginal cavity and hopefully to seal against leakage.

Because the material used necessarily is very absorbent, conventionalunmodified tampons, even in their relatively small compressed size, tendto wipe the vaginal tract dry during insertion and in so doing may causeundesirable irritation to the mucous membrane which lines the cavity.Drying of the membrane also increases frictional resistance to insertionwhich is also objectionable. In order to relieve the difiiculties andannoyances encountered during insertion, it is therefore desirable toprovide tampons having surface characteristics which reduce frictionalresistance to insertion and have a less absorbent wiping action duringinsertion, without hampering the effectiveness of the tampon inperforming its absorptive function subsequent to placement in the bodycavity.

While the desirability of having reduced frictional resistance andabsorbent wiping action applies to all forms of tampons, thesecharacteristics are particularly important for those tampon styles whichare not enclosed in the rigid telescoping tubes commonly employed as theinsertion device. For example, in using digital tampons for directfinger insertion and also in using tampons which employ a detachablestick for insertion, the absorbent surface of the tampon is normallyexposed prior to use so that it comes in direct contact with the bodytissue during insertion. Tampons with stick type inserters, which arenot enclosed in a protective tube, have advantages in that they are lesscostly to produce, yet provide a more positive means of placement.However, since the absorbent surface area of stick tampons, and thestill more economical digital style tampons, directly contacts the bodytissues during insertion, such tampons have a tendency to absorbprematurely the moisture normally present on the surface of mucoid orepithelial tissue. As stated previously, this early absorptive actiontends to dry the surface, and contributes to the difficulties involvedin tampon insertion. When tampons are used for menstrual purposes, thisdrying effect is particularly evidenced during times of light flow,especially at the beginning and at the waning days of the menstrualperiod.

Many efforts have been made to overcome these latter difficulties. Suchefforts include coating the tip or leading end of the tampon itself withlubricants such as petroleum jelly, emulsified mineral oil, soaps,surgical gel, and the like, or enclosing the tip of the tampon in awater-soluble film comprised of materials such as methyl cellulose,gelatin, dextrin, glucose, polyvinyl alcohol, sodium alginate, etc.While these prior modifications result in reduced frictional resistanceand a concomitant improvement in insertion ease, each of them tends tointerfere with the absorption capabilities of the tampon afterinsertion. Furthermore, such insertionaiding materials require anadditional manufacturing step and therefore add considerably to theproduction cost. The tampon of this invention utilizes fibers which havea slick, slippery surface as the outer component of the tampon and whichcomprise an integral part of the tampon construction before compression,thus eliminating additional steps in its manufacture.

Accordingly, the main object of the present invention is to provide anabsorbent tampon with an outer surface having frictional characteristicswhich reduce resistance to insertion.

A further object is to provide an absorbent tampon which reduces thetendency to wipe the skin dry during insertion.

Another object is to provide an absorbent tampon in which reducedfrictional resistance characteristics of the surface are obtainedwithout impairing the absorptive function of the tampon.

Still another object is to provide an absorbent compressed tampon inwhich the friction-reducing material is fibrous and is an integral partof the tampon body before compression.

SUMMARY OF THE INVENTION The tampon of this invention generallycomprises an elongated cylindrical body of compressed absorbent materialhaving a liquid-pervious overlay of polypropylene fibers. The overlaypreferably comprises and overwrapping web of non-woven construction inwhich the fibers are bonded by tiny, spaced, heat embossments, or byadhesive means at the fiber crossover points. The compressed tampon ofpreferred construction is manufactured in the usual manner, startingwith an uncompressed batt of loosely felted fibers, overwrapping it witha fibrous polypropylene jacket and then compressing it to the desiredself-sustaining form of a size suitable for insertion in the vaginaltract. The surface of the polypropylene fibers in the overwrap has amuch-improved lubricity over conventional overwrap materials and as aresult the amount of force required for insertion is considerablyreduced. The reduction in insertion force being in the range of about40-60 percent when compared to prior art tampons. The polypropyleneoverwrap is sufficiently pervious to allow menstrual fluids to penetrateto the absorbent core with substantially no reduction in speed ofpenetration as compared to conventional overwraps, and withsubstantially no reduction in the absorbent capacity of the tampon. Inaddition, because the fibers are hydrophobic they do not absorb fluidsthemselves and thus decrease the tendency to wipe the mucoidal tissuedry during insertion. The latter factor also contributes to the ease ofinsertion. It will thus be seen that the invention has the advantage ofproviding an absorbent tampon with a fibrous surface which acts to easeinsertion while avoiding the disadvantages of the usual supplementaryinsertion aids formerly required.

These and other advantages, objects, and features attendant the improvedconstruction will become apparent by reference to the followingspecification and accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING In the drawing:

FIG. 1 is a perspective illustration, with surface portions cut away, ofa typical tampon body as employed in this invention and beforecompression.

FIG. 2 is a perspective illustration of the uncompressed tampon body ofFIG. 1 provided with a conventional draw string. FIG. 3 is a perspectiveillustration of a compressed tampon made from the uncompressed tamponbody of FIG. 2 and being provided with an insertion stick. FIG. 4 is alongitudinal section taken through the tampon portion only of FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the preferred embodimentsshown in the drawing, the tampon comprises an absorbent body of fibrousmaterial and a fluid-pervious outer wrapper 12 of polypropylene fibers.The absorbent body 10 may initially be rectangular in shape, asillustrated, and is usually cut to a suitable size from a continuoussupply of web of fibrous material. Other starting shapes may, of course,be used. The absorbent body may comprise any suitably formed batt offibers; a plurality of superposed fiber layers; an assembly of longfibers assembled in transverse array and secured together by a line oflongitudinal stitching; layers of cellulose wadding; absorbent sponge,or any desired combination of these.

Pervious outer wrapper 12 comprises polypropylene fibers preferably inthe form of a non-woven web bonded by spaced areas of tiny heatembossments. Chemical bonding may also be used. Alternatively, the webmay also consist of a non-woven scrim of low twist polypropylene threadswith an overlay of polypropylene fibers. Other fibers coated overallwith polypropylene are also contemplated.

In the embodiment shown, the overwrap encircles the tampon body and isoverlapped at 14. The loose ends of the overwrap are tucked into theends of the absorbent body as shown at 16.

A withdrawal string 18 is anchored to one end of the wrapped tampon inany suitable manner and extends from the rear portion thereof.

The tampon body is then compressed to an elongate cylindrical shape 19,and in the form shown in FIG. 3 has a socket 20 impressed into the rearend in which a removable insertion stick 22 is seated.

In the sectional view of FIG. 4 the relationship of wrapper l2,compressed body 10, and stick-holding socket 10 are shown.

As indicated previously, the polypropylene fiber outerwrap produces atampon surface which has markedly less frictional resistance thanconventional prior art absorbent covers. The following comparisonsinvolving conventional tampons and various embodiments of the tampon ofthis invention will more clearly illustrate the differences in surfacelubricity expressed in the amount of force required for insertion.

The tampons tested were made in accordance with the procedure describedin US. Pat. No. 2,761,449. The uncompressed body measured about 4 X l-%X inches and was compressed to a self-sustaining cylindrical formmeasuring about 144 inches in length and approximately one half inch indiameter.

The conventional control tampon was wrapped in a non-woven scrim of thetype described in US. Pat. No. 2,900,980 having a 6 X 5 thread count andweighing about 6.66 grams per square yard. The various embodiments ofthe tampons of this invention were wrapped with a non-woven web ofheat-bonded polypropylene weighing 5 grams per square yard (sample 1),10 grams per square yard (Sample 2) and l6 grams per square yard (Sample3), respectively. Compression was done at room temperature.

Samples 1A and 2A were constructed the same as Samples 1 and 2,respectively, but were compressed at approximately 200 F, which gave theexposed polypropylene fibers on the tampon surface a smoother, somewhatglazed, appearance. Another sample (Sample 4) was the same constructionas the control but was coated with a surgical gel which acted as alubricant to aid insertion.

Results were as follows:

Average Insertion Force Required I: Reduction It will be noted that thetampons having a polypropylene wrapper displayed a reduction ininsertion force ranging from 38.5 to 6l.6 percent when compared to acontrol tampon with a conventional absorbent wrapper. It is also notedthat the reduction in insertion force is well within the range of thereduction in force achieved when a conventional tampon is lubricatedwith a surgical jelly, the best previous insertion aid known.

The non-woven polypropylene wrapper preferably should be as thin aspossible but still be of a strength which permits handling duringconversion. Webs in the weight range of l to 25 grams per square yardmay be used, with the preferred range being 5 to 16 grams per squareyard. Fibers ranging in denier from 0.5 to 3 have been found useful.Other fibers may be mixed with polypropylene but as the amount ofpolypropylene present is decreased, the improvement in reduction ofinsertion force is correspondingly less. The web should permit easypenetration of fluids but should have substantially no absorptioncapacity itself. The web may also be treated with a wetting agent whichspeeds penetration of fluids during use. Non-ionic agents such as thecommercially available nonyl-phenoxypoly (ethyleneoxy) ethanols werefound particularly useful for this purpose, in amounts as small as 0.1percent by weight.

It will also be seen that instead of a separate overwrap the absorbenttampon body may be formed with a thin layer of polypropylene fibersintegrally deposited and joined to the surface of the absorbent bodyitself.

ln compressing the tampon either heated or unheated dies may be used. Itwas found that in either case the lubricity of the tampon with thepolypropylene fiber overwrap is considerably improved over conventionaltampons. However, when heat in the range of 175 to 225 F, is used, thetampon takes on a smoother glazed appearance which apparently improvesthe effective lubricity. In addition to having slightly less frictionalresistance whereby slightly less insertion force is required, whencompared with tampons made with unheated dies, the glazed tampons alsoseemed to have a psychological effect on the user who seemed convincedthat the smoother-appearing surface must necessarily insert easier thana similar polypropylene fiber surfaced tampon which has a fuzzyappearance. Accordingly, the heat-glazed embodiment is preferred.

While several specific embodiments of the inventive concept have beenset forth above, it is understood that the invention is not to beconstrued as limited thereby, and that suitable changes, modifications,and variations may be made without departing from the spirit and scopeof the invention as defined in the appended claims.

What is claimed is:

1. In a compressed tampon for intravaginal use comprising an absorbentbody enclosed in a fluid pervious fiber overlay with the entirestructure compressed to a self-sustaining cylindrical form of a size forinsertion into the vaginal canal, the improvement in which the fluidpervious overlay of said compressed structure consists of non-absorbentpolypropylene fibers, said tampon being characterized by substantiallyreduced frictional resistance to insertion into the vagina compared tothe frictional resistance to insertion of intravaginal tampons having anabsorbent surface.

2. The tampon of claim 1 in which said overlay is a web wrapper ofnon-woven fibers.

3. The tampon of claim 2 in which the fibers in said non-woven web arespot-bonded together in spaced areas comprising minute heat embossments.

4. The tampon of claim 2 in which the fibers in said non-woven web arebonded together at their crossing points by chemical adhesion.

5. The tampon of claim 1 in which said overlay is adhered to a scrim ofcross-laid low twist threads bonded together at their intersections.

6. The tampon of claim 2 in which said web is in the weight range of lto 25 grams per square yard.

7. The tampon of olairn 2 in which said web is in the weight range of 5to 16 grams per square yard.

8. The tampon of claim 1 in which the exposed polypropylene fibersdisposed on the compressed tampon surface have a glazed finish.

2. The tampon of claim 1 in which sAid overlay is a web wrapper ofnon-woven fibers.
 3. The tampon of claim 2 in which the fibers in saidnon-woven web are spot-bonded together in spaced areas comprising minuteheat embossments.
 4. The tampon of claim 2 in which the fibers in saidnon-woven web are bonded together at their crossing points by chemicaladhesion.
 5. The tampon of claim 1 in which said overlay is adhered to ascrim of cross-laid low twist threads bonded together at theirintersections.
 6. The tampon of claim 2 in which said web is in theweight range of 1 to 25 grams per square yard.
 7. The tampon of claim 2in which said web is in the weight range of 5 to 16 grams per squareyard.
 8. The tampon of claim 1 in which the exposed polypropylene fibersdisposed on the compressed tampon surface have a glazed finish.